Optical features of flax fibers coming from the Turin Shroud

摘要

This paper presents a study of flax fibers coming from the TS (Turin Shroud)udand evidences their peculiar features if compared with recent ones. A further comparisonudbetween image-fibers and non-image-fibers shows both structural and chemical differencesudespecially in correspondence of the external layer about 200 nm thick.udThe PLM (Polarized Light Microscopy) is used to evidence the various features of theudTS fibers, and these features are then explained also at the light of the ancient procedureudused to produce fibers from flax plants.udOptical microscope and SEM (Scanning Electron Microscope) are used to better showudthe various fiber’s features evidencing the presence of impurities and defects.udFinally an opto-chemical analysis is performed showing results of TS fibers relative toudCIELAB values, FT-IR ATR and Raman tests also trying to interpret, from a chemical pointudof view, some peaks present in the spectra.